Bristol 2007 (Post-Op RT Maxillary Sinus)

Background

Retrospective single-institution analysis (MD Anderson). N=146, maxillary sinus cancer treated with post-operative RT 1969–2002. Group 1 (n=90; pre-1991) vs Group 2 (n=56; post-1991). Group 2 changes: skull base coverage for PNI, elective neck RT for SCC/undifferentiated, improved dose distribution.

Interventions and follow up

Group 1 (pre-1991): conventional post-operative RT
Group 2 (post-1991): post-operative RT + skull base coverage for PNI, elective neck RT for SCC/undifferentiated, improved dose distribution
Primary endpoint: OS, local control, nodal control, distant metastasis, late toxicity
mFollow up: ~120 mo (Group 1); ~60 mo (Group 2)

Results

5-yr OS (Group 1 vs 2): 51% vs 62% (P=NS)
5-yr nodal control (SCC/UDC, elective neck RT): 93% vs 64% (P<.05)
Distant metastasis (SCC/UDC): 3% vs 20% (P<.05)
Grade 3–4 late toxicity: 8% (Group 2) vs 34% (Group 1), P=.014

Adverse events

Grade 3–4 late toxicity: 8% (Group 2) vs 34% (Group 1), P=.014
Group 1 pattern: higher radiation retinopathy, cataracts, osteoradionecrosis
Driver: improved dose distribution reducing eye/optic/brain injury
Elective neck RT (Group 2): did not increase toxicity

Conclusions

Elective neck RT for squamous histology and improved dose distribution significantly improved nodal control, reduced distant metastasis, and markedly decreased late toxicity in maxillary sinus cancer; OS gain was not statistically significant.

Key Limitations

Single-institution retrospective with era comparison (confounded by stage migration, imaging, supportive care over 33 yr); unequal follow-up; small subgroups; OS not powered.

Clinical Context

Supports elective neck irradiation for squamous/undifferentiated maxillary sinus cancer and modern conformal dose distribution to limit ocular/CNS late toxicity; foundational for IMRT-era practice.

References